Patients with thymoma have no obvious symptoms in the early stage and are mostly found by chance during physical examination. In severe cases, common symptoms include chest tightness, chest pain, cough, discomfort in the anterior thoracic region, and in patients with combined myasthenia gravis may be accompanied by eyelid or generalized skeletal muscle weakness manifestations. In normal adults, thymus tissue is rare or completely degenerated. If pathological hyperplasia occurs, it can lead to thymoma, which can be benign or malignant. Most small thymomas are asymptomatic and not easily detected. When the tumor increases to a certain extent, it can be accompanied by chest pain, chest tightness, cough and discomfort in the anterior chest area, which are mainly symptoms of compression or invasion, and most early patients are found during physical examination. Thymoma can be combined with certain diseases such as myasthenia gravis, aplastic anemia, nephrotic syndrome, hypoglobulinemia, rheumatoid arthritis, systemic lupus erythematosus, etc., which are all specific symptoms. In summary, most patients with thymoma have no clinical manifestations and are found mainly through physical examination. In a few patients, the tumor enlarges to a certain extent and causes compression or invasive symptoms, resulting in chest pain, chest tightness, cough or discomfort in the anterior chest area. Some of them can be accompanied by droopy eyelids or muscle weakness.